This invention relates to an improvement in a digital-type exposure meter for photography.
Hitherto, as exposure meters for photographic use, analogue-type devices having an ammeter for indicating the exposure value have been generally used. Recently, as a result of rapid development of integrated circuits, digital-type exposure meters having several lamps or light-emitting diodes for indicating exposure values are becoming more and more popular. One example of such conventional digital-type exposure meters is shown in U.S. Pat. No. 3,807,879 to Mori.
In such a conventional digital-indication type exposure meter, the exposure values to be indicated are discrete, for instance, at 2 times, 4 times, 8 times, . . . and each value is respectively indicated by each corresponding lamp or light-emitting diode. In the circuitry for providing digital values of exposure steps, the above-mentioned prior art comprises a row of resistors of predetermined resistances corresponding to steps of exposure values. Such resistors of specified resistances are required to be precise, and therefore, are expensive.